Consistent with the "system" model, EATS maintains a 3 layer basic contextual model:
- Center focus area layer defines the "system under study"
- Contextual layer defines the environment for the system
- Sub-component layer defines constituent parts of concern to the study
Each of these three layers, can be sub-divided to deal with content on a multi-layer, logical layered basis, as needed for the specifics of the element and the model.
An alternative visualization is to think in terms of nested containers.